Neoadjuvant PD-L1 plus CTLA-4 blockade in patients with cisplatin-ineligible operable high-risk urothelial carcinoma

Clinical experience with CTLA-4 blockade for cancer immunotherapy: From the monospecific monoclonal antibody ipilimumab to probodies and bispecific molecules targeting the tumor microenvironment

The immune checkpoint cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is an inhibitory regulator of T-cell mediated responses that has been investigated as target of monoclonal antibodies (mAbs) for cancer immunotherapy. The anti-CTLA-4 mAb ipilimumab represents the first immune checkpoint inhibitor that significantly improved overall survival in patients with unresectable/metastatic melanoma. The subsequent approved indications (often in the first-line setting) for melanoma and other advanced/metastatic solid tumors always require ipilimumab combination with nivolumab, an anti-programmed cell death protein 1 (PD-1) mAb. However, the improved clinical efficacy of the mAb combination is associated with increased immune-related adverse events, which might require treatment discontinuation even in responding patients. This drawback is expected to be overcome by the recent development of anti-CTLA-4 probodies proteolitycally activated in the tumor microenvironment and bispecific molecules targeting both CTLA-4 and PD-1, whose co-expression is characteristic of tumor-infiltrating T cells. These molecules would preferentially stimulate immune responses against the tumor, reducing toxicity toward normal tissues.

Evaluation of lymphocyte-specific programmed cell death protein 1 receptor expression and cytokines in blood and urine in canine urothelial carcinoma patients

Urothelial carcinoma (UC) is the most common urinary tumour in dogs. Despite a range of treatment options, prognosis remains poor in dogs. In people, breakthroughs with checkpoint inhibitors have established new standards of care for muscle-invasive bladder cancer patients and elevated levels of programmed cell death protein 1 (PD-1) suggest immune checkpoint blockade may be a novel target for therapy. The goal of this study was to determine if canine UC patients express elevated levels of lymphocyte-specific PD-1 and/or urinary cytokine biomarkers compared to healthy dogs. Paired blood and urine were evaluated in 10 canine UC patients, five cystitis patients and 10 control dogs for lymphocyte-specific PD-1 expression via flow cytometry and relative cytokine expression. In UC patients, PD-1 expression was significantly elevated on CD8⁺ lymphocytes in urine samples. UC patients had a higher CD4:CD8 ratio in their urine compared to healthy dogs, however, there was no significant variation in the CD8:Treg ratio between any group. Cystitis patients had significantly elevated levels of CD4⁺ T cells, CD8⁺ T cells and Tregs in their blood samples compared to UC patients and healthy dogs. Cytokine analysis demonstrated significant elevations in urinary cytokines (granulocyte-macrophage colony-stimulating factor, interferon-gamma [IFN-γ], interleukin (IL)-2, IL-6 IL-7, IL-8 and IL-15, IP-10, KC-like, IL-18, monocyte chemoattractant protein-1 and tumour necrosis factor-alpha). Several of these cytokines have been previously correlated with both lymphocyte-specific PD-1 expression (IFN-γ, IL-2, IL-7 and IL-15) in muscle-invasive urothelial carcinoma in humans. Our results provide evidence of urinary lymphocyte PD-1 expression and future studies could elucidate whether veterinary UC patients will respond favourably to anti-PD-1 immune checkpoint inhibitor therapy.

Clinical benefit of neoadjuvant anti-PD-1/PD-L1 utilization among different tumors

PD‐1/PD‐L1 (programmed cell death‐1 and programmed death‐ligand 1) inhibitors utilization in neoadjuvant therapy has been assessed in tumors. This study focused on the clinical benefits of neoadjuvant anti‐PD‐1/PD‐L1 therapy. A comprehensive search was conducted in electronic databases to identify eligible studies. Major response rate (MRR) and complete response rate (CRR) were pooled in this analysis to assess the efficacy of neoadjuvant anti‐PD‐1/PD‐L1 utilization, all grades and high‐grade adverse events (AEs) were pooled to evaluate its safety. Twenty studies were included in this meta‐analysis, with 828 patients suffering from different tumors. The pooled CRR of triple‐negative breast cancer was 0.569 (95% CI 0.514, 0.624, I² = 0%) and the pooled MRR of lung cancer was 0.471 (95% CI 0.267, 0.575, I² = 0%). The most frequent adverse event was fatigue (0.272 95% CI 0.171, 0.402, I² = 87%), and the most common high‐grade adverse event was febrile neutropenia (0.084 95% CI 0.063, 0.112, I² = 85%). In conclusion, neoadjuvant anti‐PD‐1/PD‐L1 therapy received satisfactory clinical results in these tumors included.

Neoadjuvant Therapy Using Checkpoint Inhibitors before Radical Cystectomy for Muscle Invasive Bladder Cancer: A Systematic Review

Background: Neoadjuvant chemotherapy is the standard of care before radical cystectomy for muscle invasive bladder cancer. Recently, checkpoint inhibitors have been investigated as a neoadjuvant treatment after the reported efficacy of checkpoint inhibitors in metastatic urothelial carcinoma. Objectives: The aim of this systematic review is to investigate the role of checkpoint inhibitors as a neoadjuvant treatment for muscle invasive bladder cancer before radical cystectomy. Methods: Based on the PRISMA statement, a systematic review of the literature was conducted through online databases and the American Society of Clinical Oncology (ASCO) Meeting Library. Suitable publications were subjected to full-text assessment. The primary outcome of this review was to identify the impact of neoadjuvant immunotherapy on the oncological outcomes and survival benefits. Results: From the retrieved 254 results, 8 studies including 404 patients were included. Complete response varied between 30% and 50%. Downstaging varied between 50% and 74%. ≥Grade 3 AEs were recorded in 8.6% of patients who received monotherapy with either Atezolizumab or Pembrolizumab. In patients who received combination treatment, the incidence of ≥Grade 3 AEs was 16.3% for chemoimmunotherapy and 36.5% for combined immunotherapy. A total of 373 patients (92%) underwent radical cystectomy. ≥Grade 3 Clavien-Dindo surgical complications were reported in 21.7% of the patients. One-year overall survival (OS) and relapse-free survival (RFS) varied between 81% and 92%, and 70% and 88%, respectively. Conclusion: The evidence on the use of immune checkpoint inhibitors in the setting of pre-radical cystectomy is quite limited, with noted variability within published trials. Combination with chemotherapy or another checkpoint inhibitor may boost response, although prospective studies with extended follow-up are needed to report on the survival advantages.

Pilot study of Tremelimumab with and without cryoablation in patients with metastatic renal cell carcinoma

Cryoablation in combination with immune checkpoint therapy was previously reported to improve anti-tumor immune responses in pre-clinical studies. Here we report a pilot study of anti-CTLA-4 (tremelimumab) with (n = 15) or without (n = 14) cryoablation in patients with metastatic renal cell carcinoma (NCT02626130), 18 patients with clear cell and 11 patients with non-clear cell histologies. The primary endpoint is safety, secondary endpoints include objective response rate, progression-free survival, and immune monitoring studies. Safety data indicate ≥ grade 3 treatment-related adverse events in 16 of 29 patients (55%) including 6 diarrhea/colitis, 3 hepatitis, 1 pneumonitis, and 1 glomerulonephritis. Toxicity leading to treatment discontinuation occurs in 5 patients in each arm. 3 patients with clear cell histology experience durable responses. One patient in the tremelimumab arm experiences an objective response, the median progression-free survival for all patients is 3.3 months (95% CI: 2.0, 5.3 months). Exploratory immune monitoring analysis of baseline and post-treatment tumor tissue samples shows that treatment increases immune cell infiltration and tertiary lymphoid structures in clear cell but not in non-clear cell. In clear cell, cryoablation plus tremelimumab leads to a significant increase in immune cell infiltration. These data highlight that treatment with tremelimumab plus cryotherapy is feasible and modulates the immune microenvironment in patients with metastatic clear cell histology.

Role of immunotherapy in localized muscle invasive urothelial cancer

The standard treatment for non-metastatic muscle-invasive bladder cancer (MIBC) is cisplatin-based neoadjuvant chemotherapy followed by radical cystectomy or trimodality therapy with chemoradiation in select patients. Pathologic complete response (pCR) to neoadjuvant chemotherapy is a reliable predictor of overall and disease-specific survival in MIBC. A pCR rate of 35-40% is attained with neoadjuvant cisplatin-based chemotherapy. With the approval of immune checkpoint inhibitors (ICIs) for the treatment of metastatic urothelial cancer, these agents are now being studied in the neoadjuvant setting for MIBC. We describe the results from clinical trials using single agent ICI, ICI/ICI and ICI/chemotherapy combination therapies in the neoadjuvant setting for MIBC. These single-arm clinical trials have demonstrated safety and pCR comparable to cisplatin-based chemotherapy. Neoadjuvant ICI is a promising approach for cisplatin-ineligible patients, and the role of adding ICIs to cisplatin-based chemotherapy is also being investigated in randomized phase III clinical trials. Ongoing biomarker research to suggest a response to neoadjuvant ICIs will also guide appropriate treatment selection. We also describe the studies using ICIs for adjuvant therapy and in combination with chemoradiation.

Neoadjuvant programmed death-1 blockade plus chemotherapy in locally advanced esophageal squamous cell carcinoma

Background

Immunotherapy is effective in treating unresectable esophageal squamous cell carcinoma (ESCC), but little is known about its role in the preoperative setting. The aim of this study was to evaluate the safety, feasibility and efficacy of neoadjuvant treatment with camrelizumab plus chemotherapy in locally advanced ESCC.

Methods

Patients diagnosed with locally advanced ESCC were retrospectively included if they had received neoadjuvant camrelizumab plus nab-paclitaxel and S1 capsule followed by radical esophagectomy between November, 2019 and June, 2020 at Sun Yat-sen University Cancer Center. Primary endpoints were safety and feasibility. In addition, pathological response and the relationship between tumor immune microenvironment (TIME)/tumor mutational burden (TMB) and treatment response were also investigated.

Results

Twelve patients were included and they all received three courses of preoperative treatment with camrelizumab plus nab-paclitaxel/S1. No grade 3 or higher toxicities occurred. No surgical delay or perioperative death was reported. Nine patients (75%) responded to the treatment, four with a complete pathological response (pCR) and five with a major pathological response (MPR). Neither programmed death-ligand 1 (PD-L1) expression nor TMB was correlated with treatment response. TIME analysis revealed that a higher abundance of CD56dim natural killer cells was associated with better pathological response in the primary tumor, while lower density of M2-tumor-associated macrophages was associated with better pathological response in the lymph nodes (LNs).

Conclusions

Neoadjuvant camrelizumab plus nab-paclitaxel and S1 is safe, feasible and effective in locally advanced ESCC and is worth further investigation.

Immune PET Imaging

Fluorodeoxyglucose (FDG) PET/CT is sensitive to metabolic, immune-related, and structural changes that can occur in tumors in cancer immunotherapy. Unique mechanisms of immune checkpoint inhibitors (ICIs) occasionally make response evaluation challenging, because tumors and inflammatory changes are both FDG avid. These response patterns and sequelae of ICI immunotherapy, such as immune-related adverse events, are discussed. Immune-specific PET imaging probes at preclinical stage or in early clinical trials, which may help guide clinical management of cancer patients treated with immunotherapy and likely have applications outside of oncology for other diseases in which the immune system plays a role, are reviewed.

Immune Checkpoint Therapy: Tumor Draining Lymph Nodes in the Spotlights

Tumor-draining lymph nodes play a paradoxical role in cancer. Surgeons often resect these sentinel lymph nodes to determine metastatic spread, thereby enabling prognosis and treatment. However, lymph nodes are vital organs for the orchestration of immune responses, due to the close encounters of dedicated immune cells. In view of the success of immunotherapy, the removal of tumor-draining lymph nodes needs to be re-evaluated and viewed in a different light. Recently, an important role for tumor-draining lymph nodes has been proposed in the immunotherapy of cancer. This new insight can change the use of immune checkpoint therapy, particularly with respect to the use in neoadjuvant settings in which lymph nodes are still operational.

Neoadjuvant Immunotherapy for Muscle-Invasive Bladder Cancer

Background and Objectives: Facing neoadjuvant chemotherapy followed by surgery, neoadjuvant immunotherapy is an innovative concept in localized muscle-invasive bladder cancer. Herein, we performed a review of the available and ongoing evidence supporting immune checkpoint inhibitor (ICI) administration in the early stages of bladder cancer treatment. Materials and Methods: A literature search was performed on Medline and clinical trials databases, using the terms: “bladder cancer” OR “urothelial carcinoma”, AND “neoadjuvant immunotherapy” OR “preoperative immunotherapy”. We restricted our investigations to prospective clinical trials evaluating anti-PD-(L)1 and anti-CTLA-4 monoclonal antibodies. Data on efficacy, toxicity and potential biomarkers of response were retrieved. Results: The search identified 6 ICIs that were tested in the neoadjuvant setting for localized bladder cancer—4 anti-PD-(L)1 inhibitors (Pembrolizumab, Atezolizumab, Nivolumab and Durvalumab) and 2 anti-CTLA-4 inhibitors (Ipilimumab and Tremelimumab). Most of the existing literature was based on single-arm phase 2 clinical trials that included from 23 to 143 patients. The pathological complete response rate (pCR) and pathological response rate (pRR) ranged from 31% to 46% and from 55.9% to 66%, respectively. Survival data were immature at this time. The safety profile was acceptable, with severe treatment-related adverse events ranging from 6% to 41%. Conclusions: The results of early phase trials are encouraging, and more investigations are needed to strengthen the rationale for immune checkpoint inhibitor administration in localized muscle-invasive bladder cancer.

Bladder cancer: shedding light on the most promising investigational drugs in clinical trials

Introduction: Urothelial cancers (UC) include tumors of the bladder, upper tract, and proximal urethra. Bladder cancer (BC) arises from urothelial cells lining the bladder and accounts for 90-95% of UC. BC is responsible for approximately 500,000 new cases and has a dismal prognosis with 200,000 deaths annually globally. However, immune checkpoint inhibitors (ICIs) and antibody-drug conjugates are rapidly changing the treatment landscape. Novel therapies are building on this success and are being intensively investigated in clinical trials.Areas Covered: This paper examines the clinical trial data by searching Medline through January 2021 and clinicaltrials.gov and conference proceedings from the latest ASCO and ESMO meetings. We summarize the emerging data from clinical trials and offer insights into mechanisms of novel agents, nuances in clinical trial designs, and future directions.Expert Opinion: Approval of multiple ICIs, Enfortumab Vedotin (EV), Erdatfitinib and switch maintenance strategy with Avelumab, represent major advances in metastatic disease. ICI agents and EV are well poised to move forward for treating the early stages of bladder cancer. Finally, molecular characterization of the tumor offers hope for personalized treatment approaches.

Gut Microbiota and Immune Checkpoint Inhibitors-Based Immunotherapy

Application of immune checkpoint inhibitors (ICIs) is a major breakthrough in the field of cancer therapy, which has displayed tremendous potential in various types of malignancies. However, their response rates range widely in different cancer types and a significant number of patients experience immune-related adverse effects (irAEs) induced by these drugs, limiting the proportion of patients who can truly benefit from ICIs. Gut microbiota has gained increasing attention due to its emerging role in regulating the immune system. In recent years, numerous studies have shown that gut microbiota can modulate antitumor response, as well as decrease the risk of colitis due to ICIs in patients receiving immunotherapy. The present review analyzed recent progress of relevant basic and clinical studies in this area and explored new perspectives to enhance the efficacy of ICIs and alleviate associated irAEs via manipulation of the gut microbiota.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of urothelial cancer

A number of immunotherapies have been developed and adopted for the treatment of urothelial cancer (encompassing cancers arising from the bladder, urethra, or renal pelvis). For these immunotherapies to positively impact patient outcomes, optimal selection of agents and treatment scheduling, especially in conjunction with existing treatment paradigms, is paramount. Immunotherapies also warrant specific and unique considerations regarding patient management, emphasizing both the prompt identification and treatment of potential toxicities. In order to address these issues, the Society for Immunotherapy of Cancer (SITC) convened a panel of experts in the field of immunotherapy for urothelial cancer. The expert panel developed this clinical practice guideline (CPG) to inform healthcare professionals on important aspects of immunotherapeutic treatment for urothelial cancer, including diagnostic testing, treatment planning, immune-related adverse events (irAEs), and patient quality of life (QOL) considerations. The evidence- and consensus-based recommendations in this CPG are intended to give guidance to cancer care providers treating patients with urothelial cancer.

Durvalumab Plus Tremelimumab in Solid Tumors: A Systematic Review

INTRODUCTION

Cancer immunotherapy represents one of the most important innovations in modern medicine. Durvalumab is an anti-programmed cell death ligand 1 (PDL-1) agent which is currently under investigation in several studies in combination with the anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4) drug tremelimumab. The aim of this review was to systematically identify and revise the current scientific literature investigating the combination of these two drugs in solid tumors.

METHODS

A digital search on the Medline (PubMed interface) and Scopus databases for articles published from inception to 26 February 2021 was performed. The terms used for the search were durvalumab AND tremelimumab. Trials reported in English involving adult patients with solid cancers treated with the combination durvalumab plus tremelimumab were retrieved; the references of the articles were cross-checked to identify missing papers.

RESULTS

The electronic search produced 267 results; after exclusion of duplicates, irrelevant articles, reviews, and papers not in English or missing data, 19 articles were included for revision. The total number of patients treated with the combination of durvalumab and tremelimumab in the studies retrieved was 2052.

CONCLUSION

The combination of durvalumab plus tremelimumab showed some oncological advantages in comparison with traditional chemotherapies in some subsets of tumors, but generally has not shown consistent advantages in comparison with the employment of durvalumab monotherapy. A number of the studies examined had intrinsic methodological limitations; therefore, future well-designed studies involving larger cohorts are warranted.

The 12-CK Score: Global Measurement of Tertiary Lymphoid Structures

There is emerging evidence that the adaptive anti-tumor activity may be orchestrated by secondary lymphoid organ-like aggregates residing in the tumor microenvironment. Known as tertiary lymphoid structures, these lymphoid aggregates serve as key outposts for lymphocyte recruitment, priming and activation. They have been linked to favorable outcomes in many tumor types, and more recently, have been shown to be effective predictors of response to immune checkpoint blockade. We have previously described a 12-chemokine (12-CK) transcriptional score which recapitulates an overwhelming enrichment for immune-related and inflammation-related genes in colorectal carcinoma. Subsequently, the 12-CK score was found to prognosticate favorable survival in multiple tumors types including melanoma, breast cancer, and bladder cancer. In the current study, we summarize the discovery and validation of the 12-CK score in various tumor types, its relationship to TLSs found within the tumor microenvironment, and explore its potential role as both a prognostic and predictive marker in the treatment of various cancers.

Neoadjuvant Immunotherapy: The Next Gold Standard Before Radical Surgery for Urothelial Cancer

Cisplatin-based chemotherapy followed by radical cystectomy with bilateral pelvic lymph-node dissection is the current standard for cT2–4a N0 M0 urothelial bladder cancer. Immune checkpoint inhibitors have recently been tested in the neoadjuvant setting with promising pathological and survival results and a better safety profile. Excellent pathological responses have been observed, especially in cases with higher clinical T stage and PD-L1 expression, in addition to patients with selected gene signatures. In biomarker-selected patients, this manageable approach has the potential to become a new treatment option in the near future.

Patient summary

For patients with bladder cancer invading the bladder wall muscle, platinum-based chemotherapy has been the standard treatment. Increasing evidence suggests that an alternative first treatment for this disease could be immunotherapy. Novel biomarkers and further studies are needed to support this approach before it can be used in everyday clinical practice.

Comparison of Oncologic Outcomes of Dose-Dense Methotrexate, Vinblastine, Doxorubicin, and Cisplatin (ddMVAC) with Gemcitabine and Cisplatin (GC) as Neoadjuvant Chemotherapy for Muscle-Invasive Bladder Cancer: Systematic Review and Meta-Analysis

Simple Summary

Currently, platinum-based neoadjuvant chemotherapy (NAC) is becoming a standard treatment for use in patients with muscle-invasive bladder cancer. However, comparisons of oncologic outcomes for the two most commonly used NAC regimens, ddMVAC (dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin) and GC (gemcitabine and cisplatin), are controversial. We sought to compare the oncologic outcomes of these two regimens via a systematic review and meta-analysis of all the available studies published to date. Through this, we aimed to provide evidence on the optimal NAC regimen for use in muscle-invasive bladder cancer.

Abstract

Platinum-based neoadjuvant chemotherapy (NAC) is widely used for treating muscle-invasive bladder cancer (MIBC). A systematic review was performed following PRISMA guidelines. PubMed, Embase, and the Cochrane Library were searched up to December 2020. We conducted a meta-analysis to compare the oncologic outcomes of ddMVAC (dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin) and GC (gemcitabine and cisplatin), which are the most widely used NAC regimens. Endpoints included pathologic complete response (pCR), pathologic downstaging (pDS), overall survival (OS), and cancer-specific survival (CSS). Five studies, with a total of 1206 patients, were included for meta-analysis. pCR was observed in 35.2% of the ddMVAC arm and in 25.1% of the GC arm, and pCR was significantly higher in ddMVAC than in GC (odds ratio (OR), 1.45; 95% confidence interval (CI), 1.11–1.89; p = 0.006). There was no significant difference in pDS (OR, 1.37; CI, 0.84–2.21; p = 0.20). OS was significantly higher in ddMVAC than in GC (hazard ratio, 2.16; CI, 1.42–3.29; p = 0.0004). Only one study reported CSS outcomes. The results of this analysis indicate that ddMVAC is superior to GC in terms of pCR and OS, suggesting that ddMVAC is more effective than GC in NAC for MIBC. However, this should be interpreted with caution because of the inherent limitations of retrospective studies.

Tertiary lymphoid structure signatures are associated with survival and immunotherapy response in muscle-invasive bladder cancer

Immunotherapy that block PD-1–PD-L1 pathway can induce durable tumor control and result in the long-term survival of patients with advanced bladder cancers. However, these responses only occur in a subset of patients. We study gene expression profiles in 1763 muscle-invasive bladder cancers (MIBCs) and 11,835 solid tumors from TCGA. We establish an immune-based classification on the basis of the composition of the tumor microenvironment and identify six distinct phenotypes. The class F was characterized by a strong tertiary lymphoid structures (TLSs) related gene expression signature. Pan-cancer gene expression analysis of tertiary lymphoid structure markers in 11,835 solid tumors from TCGA unveiled the heterogeneity of TLSs abundance both within and between human cancer types. The class F group demonstrated improved survival and a high response rate to PD1 blockade. This work confirms the immune subtypes in patients with MIBC, and unravels the potential of TLS signatures to guide clinical decision-making and treatments.

Current Perioperative Therapy for Muscle Invasive Bladder Cancer

Radical cystectomy is curative in only approximately 50% of patients with muscle-invasive bladder cancer. Although perioperative radiotherapy has been tested with the intent of improving locoregional disease control, there currently is no role for this modality in routine care. Perioperative systemic therapy is used with the intent of reducing the risk of systemic recurrence. Robust trial evidence supports the use of neoadjuvant cisplatin-based chemotherapy, with adjuvant chemotherapy offered as an alternative if neoadjuvant therapy is not administered. Perioperative immunotherapy represents the next frontier in perioperative therapy. Further biomarker development is required to guide treatment in individual patients.

Immune checkpoint inhibitors for BCG-resistant NMIBC: the dawn of a new era

INTRODUCTION

High risk non-muscle invasive bladder cancer (NMIBC) is a recurring and potentially lethal disease. To date, with the exception of radical surgery, there are no validated strategies for patients not responding to intravesical BCG therapy. Immune checkpoint inhibitors (ICI) are currently being tested for BCG-resistant NMIBC. We report current available data and ongoing trials exploring the efficacy and safety of ICI in this setting.

EVIDENCE ACQUISITION

A narrative search was performed including the combination of the following words: ("immunotherapy") AND ("BCG" AND "resistant" OR "non-muscle AND invasive") AND ("bladder AND "cancer"). Three search engines: PubMed, Embase and Web of Science were queried up to November 1, 2020. Congress abstracts reporting results and not only trials' design were also referenced. The US National Library of Medicine was queried via clinicaltrials.gov to explore ongoing trials on the subject.

EVIDENCE SYNTHESIS

Pembrolizumab demonstrated a promising 40.6% (95% CI: 30.7-51.1) complete response within the KEYNOTE-057, with a median duration of response of 16.2 months. Preliminary data in the phase II SWOG S1605 trial with atezolizumab showed a 41.1% complete response at 3 months. Avelumab is being tested in the PREVERT phase II study exploring ICI with radiotherapy (60-66 Gy) of the whole bladder. CheckMate 9UT analyzes nivolumab monotherapy versus nivolumab + BMS-986205 (IDO-1 inhibitor) with or without BCG in patients with BCG-unresponsive, carcinoma in situ with or without papillary component. Finally, durvalumab is being studied in the BCG resistant space with radiotherapy in the ADAPT-BLADDER study. After proving its safety profile in the phase 1, the trial will randomize patients to durvalumab + BCG, durvalumab + radiation therapy (6Gy 3×) or BCG rechallenge.

CONCLUSIONS

Pembrolizumab has received FDA approval in the treatment of BCG-resistant NMIBC. All five other ICI molecules are currently being extensively tested within clinical trials. The results of the currently ongoing studies are awaited with impatience by the uro-oncologic community and will probably open a new era in the treatment of BCG-resistant NMIBC.

Renal function outcomes in patients with muscle-invasive bladder cancer treated with neoadjuvant pembrolizumab and radical cystectomy in the PURE-01 study

The use of pembrolizumab has been largely accepted in several advanced types of cancers. PURE 01 study (NCT02736266) enrolled consecutively 143 patients with muscle-invasive bladder cancer who received 3 cycles of pembrolizumab 200 mg every 3 weeks before planned radical cystectomy (RC). Clinical, pathological and laboratory data were collected to investigate the relationship between renal function, immunotherapy and cancer-related outcomes. Serum creatinine and estimated glomerular filtration rate (eGFR) using Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine-equation 2009 were reported at baseline and after every cycle of pembrolizumab; the T stage from clinical classification TNM (cTNM) was stated before the treatment. Our analysis did not demonstrate a significant impairment of eGFR after any cycle of pembrolizumab, neither in the overall cohort nor in subgroups considering the T stages or the CKD G-categories according to K-DIGO 2012 classification. In conclusion, in neoadjuvant setting before RC our results suggest that pembrolizumab administration is safe for renal function preservation.

Tertiary lymphoid structures marker CXCL13 is associated with better survival for patients with advanced-stage bladder cancer treated with immunotherapy

INTRODUCTION

Immune checkpoint inhibitors (ICIs) have proved to be an effective treatment for up to 40% of muscle-invasive bladder cancer (MIBC), but there is still a need for better performing biomarkers allowing to improve prediction of response to ICI. Response to immunotherapy in soft-tissue sarcoma, melanoma and renal cell carcinoma have been recently linked to the presence of tertiary lymphoid structures (TLS) in the tumour. TLS are organised aggregates of T, B and dendritic cells, participating in adaptive antitumor immune response. The chemokine CXCL13 is involved in the formation of TLS, and is reported as a reliable transcriptomic marker of TLS.

OBJECTIVES

In this study, we sought to assess whether CXCL13 transcript expression can be a prognostic biomarker for ICI-treated MIBC patients and also investigated whether it can serve a biomarker of TLS in MIBC.

METHODS

We analysed transcriptomic data from three publicly available MIBC cohorts and evaluated pathological slides from the TCGA-BLCA cohort for TLS presence and stage of maturation.

RESULTS

We showed that CXCL13 was independently associated with both prolonged survival (HR = 0.8, 95% CI [0.68-0.94]) and objective response (p < 0.0001) in patients treated with ICI, at the difference of others immunological signatures. However, it was not a predictor for non-ICI-treated MIBC, suggesting a predictive effect of ICI efficacy. Finally, we validated that CXCL13 expression was correlated with tumour TLS in TCGA data set (p < 0.001), and can serve as a marker of TLS in bladder cancer.

CONCLUSION

These results support that CXCL13 expression, as a surrogate for tumour TLS, is a relevant candidate predictive biomarker of response to ICI for patients with advanced-stage bladder cancer.

Is There a Benefit of Combining Immunotherapy and Radiotherapy in Bladder Cancer?

Immune checkpoint inhibitors have transformed the management of patients with metastatic urothelial cancer, by leading to long-term response and prolongation of survival in a subset of patients. Unfortunately, only one in five patients with metastatic urothelial cancer responds to anti-programmed death ligand-1 ([AQ1]anti-PD-1) monotherapy. Preclinical and early clinical evidence indicates that radiotherapy not only acts locally, but also exerts systemic anti-tumour effects by modulating the immune system. It is hypothesised that combining checkpoint inhibitors with radiotherapy might enhance an anti-tumour immune response and increase response rates. So far, a handful of early phase clinical trials have been performed seeking to answer this question in urothelial cancer patients. The current review summarises the available preclinical and clinical evidence on radiotherapy/immunotherapy combinations in locally advanced and metastatic bladder cancer and suggests future avenues worthy of exploration.

Germinal center reactions in tertiary lymphoid structures associate with neoantigen burden, humoral immunity and long-term survivorship in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) has traditionally been thought of as an immunologically quiescent tumor type presumably because of a relatively low tumor mutational burden (TMB) and poor responses to checkpoint blockade therapy. However, many PDAC tumors exhibit T cell inflamed phenotypes. The presence of tertiary lymphoid structures (TLS) has recently been shown to be predictive of checkpoint blockade response in melanomas and sarcomas, and are prognostic for survival in PDAC. In order to more comprehensively understand tumor immunity in PDAC patients with TLS, we performed RNA-seq, single and multiplex IHC, flow cytometry and predictive genomic analysis on treatment naïve, PDAC surgical specimens. Forty-six percent of tumors contained distinct T and B cell aggregates reflective of “early-stage TLS” (ES-TLS), which correlated with longer overall and progression-free survival. These tumors had greater CD8⁺ T cell infiltration but were not defined by previously published TLS gene-expression signatures. ES-TLS⁺ tumors were enriched for IgG1 class-switched memory B cells and memory CD4⁺ T cells, suggesting durable immunological memory persisted in these patients. We also observed the presence of active germinal centers (mature-TLS) in 31% of tumors with lymphocyte clusters, whose patients had long-term survival (median 56 months). M-TLS-positive tumors had equivalent overall T cell infiltration to ES-TLS, but were enriched for activated CD4⁺ memory cells, naive B cells and NK cells. Finally, using a TCGA-PDAC dataset, ES-TLS⁺ tumors harbored a decreased TMB, but M-TLS with germinal centers expressed significantly more MHCI-restricted neoantigens as determined by an in silico neoantigen prediction method. Interestingly, M-TLS⁺ tumors also had evidence of increased rates of B cell somatic hypermutation, suggesting that germinal centers form in the presence of high-quality tumor neoantigens leading to increased humoral immunity that confers improved survival for PDAC patients.

AbbreviationsTLS: tertiary lymphoid structures; GC: germinal center(s); PDAC: pancreatic ductal adenocarcinoma; RNA-seq: RNA sequencing; BCRseq: B cell receptor sequencing; HEV: high endothelial venule; PNAd: peripheral node addressin; TMB: tumor mutational burden; TCGA: the cancer genome atlas; PAAD: pancreatic adenocarcinoma; FFPE: formalin fixed paraffin embedded; TIME: tumor immune microenvironment.

Coming of Age of Immunotherapy of Urothelial Cancer

Following platinum-based regimens becoming the reference standard of care, it has taken almost four decades to find a systemic treatment that improved overall survival in metastatic urothelial tumors. Single-agent immune checkpoint inhibitors have not only improved overall survival but also the quality of life of patients with metastatic urothelial tumors after failure of platinum-based regimens and as a maintenance therapy after four to six cycles of standard first-line chemotherapy. In addition, very promising data are emerging when single-agent immunotherapy is offered as adjuvant or neoadjuvant treatment for patients with muscle-invasive disease and also in the non-muscle-invasive setting. There is an extensive debate about the role of PD-L1 expression as a reliable biomarker to predict the activity of immune-based regimens. Furthermore, the lack of consensus concerning its utility means that there is a need for more and better tools to identify patients who are likely to benefit from these novel approaches. The field of urothelial tumors now additionally exploits novel antibody-drug conjugates and fibroblast growth factor-receptor inhibitors that are being tested in combination with immunotherapy. This added complexity contributes to an enormous increase in the challenges that will be faced shortly.

Perioperative Immunotherapy in Muscle-invasive Bladder Cancer

Immune checkpoint inhibitors (ICIs) have already been approved for the treatment of metastatic urothelial carcinoma and are now being investigated for perioperative treatment of muscle-invasive bladder cancer (MIBC). Ongoing trials are assessing ICIs as monotherapy and in combination with other treatments. Early data are promising, and long-term survival data are awaited to confirm the potential of ICIs in MIBC.

The Immunoscore in Localized Urothelial Carcinoma Treated with Neoadjuvant Chemotherapy: Clinical Significance for Pathologic Responses and Overall Survival

Simple Summary

The prognosis of localized muscle-invasive bladder cancer is poor and the prognostic and predictive biomarkers of the response to treatment are lacking. We retrospectively investigated the role of the Immunoscore in the neoadjuvant setting, where the Immunoscore is a standardized quantitative assay of lymphocytes in the tumor microenvironment. We found it allowed for the stratification of patient prognoses and the prediction of response to neoadjuvant chemotherapy.

Abstract

(1) Background—The five-year overall survival (OS) of muscle-invasive bladder cancer (MIBC) with neoadjuvant chemotherapy and cystectomy is around 50%. There is no validated biomarker to guide the treatment decision. We investigated whether the Immunoscore (IS) could predict the pathologic response to neoadjuvant chemotherapy and survival outcomes. (2) Methods—This retrospective study evaluated the IS in 117 patients treated using neoadjuvant chemotherapy for localized MIBC from six centers (France and Greece). Pre-treatment tumor samples were immunostained for CD3+ and CD8+ T cells and quantified to determine the IS. The results were associated with the response to neoadjuvant chemotherapy, time to recurrence (TTR), and OS. (3) Results—Low (IS-0), intermediate (IS-1–2), and high (IS-3–4) ISs were observed in 36.5, 43.7, and 19.8% of the cohort, respectively. IS was positively associated with a pathologic complete response (pCR; p-value = 0.0096). A high IS was found in 35.7% of patients with a pCR, whereas it was found in 11.3% of patients without a pCR. A low IS was observed in 48.4% of patients with no pCR and in 21.4% of patients with a pCR. Low-, intermediate-, and high-IS patients had five-year recurrence-free rates of 37.2%, 36.5%, and 72.6%, respectively. In the multivariable analysis, a high IS was associated with a prolonged TTR (high vs. low: p = 0.0134) and OS (high vs. low: p = 0.011). (4) Conclusions—This study showed the significant prognostic and predictive roles of IS regarding localized MIBC.

Emerging Roles of Urine-Derived Components for the Management of Bladder Cancer: One Man's Trash Is Another Man's Treasure

Simple Summary

Urinary bladder cancer (UBC) is one of the most common and deadly cancers worldwide, with many patients not responding to chemotherapy, or presenting with serious adverse effects after chemotherapy. Yet, current bench side assays provide limited accuracy for predicting therapeutic response to chemotherapeutic drugs. The aim of this review is to demonstrate the potential of urinary-derived extracellular vesicles and UBC-organoids to serve as predictive biomarkers for this cancer. Specifically, molecular subtyping of urine-derived extracellular vesicles has the potential to provide insights into the molecular stratification of the tumor, while urinary organoids will allow for individualized chemotherapy testing in the context of precision medicine.

Abstract

Urinary bladder cancer (UBC) is the most common malignancy of the urinary tract in humans, with an estimated global prevalence of 1.1 million cases over 5 years. Because of its high rates of recurrence and resistance to chemotherapy, UBC is one of the most expensive cancers to treat, resulting in significant health care costs. The development of innovative molecular and cellular tools is necessary to refine patient stratification and help predict response to treatment. Urine is an underused resource of biological components shed from bladder tumors, such as exfoliated cells and extracellular vesicles, that could serve as molecular fingerprints and provide valuable biological insights into tumor phenotype and mechanisms of resistance to chemotherapy. Additionally, characterization of urine-derived extracellular vesicles and cells could be used as reliable biomarkers for prediction of response to neoadjuvant therapy.

Recent advances in neoadjuvant immunotherapy for urothelial bladder cancer: What to expect in the near future

Urothelial bladder cancer (UC) is the most common malignancy involving the urinary system and represents a significant health problem. Immunotherapy has been used for decades for UC with intravesical bacillus Calmette-Guérin (BCG) set as the standard of care for non-muscle-invasive bladder cancer (NMIBC). The advent of immune checkpoint inhibitors (ICIs) has completely transformed the treatment landscape of bladder cancer enabling to expand the treatment strategies. Novel ICIs have successfully shown improved outcomes on metastatic disease to such an extent that the standard of care paradigm has changed leading to the development of different trials with the aim of determining whether ICIs may have a role in early disease. The localized muscle-invasive bladder cancer (MIBC) scenario remains challenging since the recurrence rate continues to be high despite all therapeutic efforts. This article will review the current experience of ICIs in the neoadjuvant setting of UC, the clinical trials landscape and finally, an insight of what to expect in the immediate and mid-term future.

Landscape of Immunotherapy in Genitourinary Malignancies

The past decade has witnessed a revolution in the development of immune checkpoint inhibitors for the treatment of multiple tumor types, including genitourinary cancers. Immune checkpoint inhibitors have notably improved the treatment outcomes of patients with metastatic renal cell carcinoma and metastatic urothelial carcinoma. In prostate cancer, the role of immunotherapy with checkpoint inhibitors is not yet established except for microsatellite instability high (MSI-H) tumors. Other immunotherapeutic approaches that have been explored in these malignancies include cytokines, vaccines, and cellular therapy. Ongoing studies are exploring the use of immunotherapy combinations as well as combination with chemotherapy and targeted therapy in these types of tumors. The use of immunotherapy beyond the metastatic setting is an active area of research. Moreover, there is great interest in biomarker development to predict response to immunotherapy and risk of toxicity. This book chapter is a comprehensive review of immunotherapeutic approaches, both approved and investigational, for the treatment of renal cell carcinoma, urothelial carcinoma, and prostate cancer.

Rationale and Outcomes for Neoadjuvant Immunotherapy in Urothelial Carcinoma of the Bladder

CONTEXT

Immune therapy has emerged as a powerful treatment of metastatic urothelial carcinoma. Over 20 ongoing studies are exploring this strategy in the neoadjuvant setting in patients with localized muscle-invasive bladder cancer.

OBJECTIVE

To summarize the rationale and the clinical outcomes regarding the use of immune checkpoint blockade in the neoadjuvant setting before radical cystectomy.

EVIDENCE ACQUISITION

A systematic review of the literature in the MEDLINE database was performed. The central search strategy used the terms bladder cancer, urothelial carcinoma, mice, human, immunotherapy, neoadjuvant therapy, atezolizumab, pembrolizumab, durvalumab, nivolumab, avelumab, ipilimumab, and tremelimumab. The search was limited to publications between January 2008 and February 2020. Publicly available relevant abstracts from recent meetings were also included.

EVIDENCE SYNTHESIS

Phase II trials investigating neoadjuvant immune checkpoint blockade as a single agent before radical cystectomy reported a rate of pathological complete response (CR), ranging from 31% with an anti-PD-L1 monoclonal antibody (mAb) atezolizumab (n = 27/88) to 37% with anti-PD-1 mAb pembrolizumab (n = 42/114). Overall, 92% (n = 87/95) and 98% (n = 112/114) of the patients underwent radical cystectomy. Neoadjuvant immune checkpoint blockade did not delay planned surgery. Checkpoint inhibitor monotherapy was well tolerated, with no unexpected toxicity in the presurgical setting. Early phase I/II trials investigating neoadjuvant combination chemotherapy strategies with immune checkpoint blockers reported enhanced antitumor efficacy, with a pathological CR ranging from 33% to 50%.

CONCLUSIONS

Although limited clinical data are available on long-term survival, neoadjuvant immune checkpoint blockade demonstrated effective antitumor efficacy for localized muscle-invasive bladder cancer. Phase III trials are currently investigating this strategy in the presurgical setting.

PATIENT SUMMARY

Immunotherapy prior to surgery has been evaluated for patients with muscle-invasive bladder cancer. Although long-term survival benefit is unknown, such treatment strategy revealed a promising antitumor response rate for patients who underwent radical cystectomy. Ongoing prospective clinical trials will define the potential advantage of this approach over current cisplatin-based chemotherapeutic regimens alone or in combination.

Hot or Not: Tumor Mutational Burden (TMB) as a Biomarker of Immunotherapy Response in Genitourinary Cancers

Pembrolizumab was recently approved for treatment of cancers with high tumor mutational burden (TMB). We conduct a focused literature review of TMB as a predictive biomarker. TMB quantifies the sum of nonsynonymous coding mutations (typically single nucleotide substitutions and short insertion-deletions) per megabase of sequenced DNA. As a proxy for expression of immunogenic neoantigens, TMB may be an effective predictive biomarker for response to immune checkpoint inhibitors. However, like other biomarkers in this setting, TMB has many limitations; the effect of this FDA approval in the current management of genitourinary cancers is likely limited to select situations.